Example embodiments of the inventive concept relate to semiconductor devices and methods of fabricating the same.
Semiconductor devices may be required to have higher integration, higher density, lower power consumption, and/or faster operating speeds. A semiconductor device with highly integrated circuits may include a multi-layered interconnection structure, which may be formed of a metal material (e.g., aluminum). The formation of the aluminum interconnection lines may include depositing an aluminum layer on an insulating layer and etching it to expose the insulating layer.
However, copper (instead of aluminum) may be increasingly used as a material for the interconnection line as a design rule of the semiconductor devices decreases. This may be due to the relatively high electrical resistivity of aluminum. For example, as a width of an aluminum interconnection line decreases, its resistance increases, and thus it may be difficult to realize semiconductor devices with higher operating speeds. Copper may offer advantages in cost and electrical conductivity, but there may be difficulty in patterning a copper layer using an etching technique. A damascene process may also be used to form copper interconnection lines.
Further, due to the increasing integration density of semiconductor devices, the spacing between interconnection lines may become narrower, which may result in electrical interference between interconnection lines and/or a delay in a signal transfer speed, despite the use of the copper interconnection lines.